implement Unlock by Samsung Fingerprint (Pass SDK)

.gitmodules

@@ -0,0 +1,6 @@
+[submodule "SamsungPass"]
+	path = SamsungPass
+	url = https://github.com/sraiteri/Xamarin-Samsung-Pass.git
+[submodule "src/SamsungPass"]
+	path = src/SamsungPass
+	url = https://github.com/sraiteri/Xamarin-Samsung-Pass.git

src/KeePass.sln

@@ -47,6 +47,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "AncientIconSet", "AncientIc
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "FingerprintTest", "FingerprintTest\FingerprintTest.csproj", "{52C0A0E7-D625-44BE-948E-D98BC6C82F0F}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SamsungPass", "SamsungPass\Xamarin.SamsungPass\SamsungPass\SamsungPass.csproj", "{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -524,6 +526,24 @@ Global
 		{52C0A0E7-D625-44BE-948E-D98BC6C82F0F}.ReleaseNoNet|Mixed Platforms.Deploy.0 = Release|Any CPU
 		{52C0A0E7-D625-44BE-948E-D98BC6C82F0F}.ReleaseNoNet|Win32.ActiveCfg = Release|Any CPU
 		{52C0A0E7-D625-44BE-948E-D98BC6C82F0F}.ReleaseNoNet|x64.ActiveCfg = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Debug|Mixed Platforms.ActiveCfg = Debug|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Debug|Mixed Platforms.Build.0 = Debug|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Debug|Win32.ActiveCfg = Debug|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Release|Any CPU.Build.0 = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Release|Mixed Platforms.ActiveCfg = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Release|Mixed Platforms.Build.0 = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Release|Win32.ActiveCfg = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.Release|x64.ActiveCfg = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.ReleaseNoNet|Any CPU.ActiveCfg = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.ReleaseNoNet|Any CPU.Build.0 = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.ReleaseNoNet|Mixed Platforms.ActiveCfg = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.ReleaseNoNet|Mixed Platforms.Build.0 = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.ReleaseNoNet|Win32.ActiveCfg = Release|Any CPU
+		{3A4B8E88-FA9B-4663-BCDA-21C12E3AF98A}.ReleaseNoNet|x64.ActiveCfg = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

src/SamsungPass

@@ -0,0 +1 @@
+Subproject commit 1495b1ad7914fa2be69e111b90039770d101aa3d

src/keepass2android/FingerprintModule.cs

@@ -17,6 +17,12 @@ using Javax.Crypto.Spec;
 
 namespace keepass2android
 {
+	public interface IFingerprintAuthCallback
+	{
+		void OnFingerprintAuthSucceeded();
+		void OnFingerprintError(string toString);
+	}
+
 	public class FingerprintModule
 	{
 		public Context Context { get; set; }
@@ -106,7 +112,7 @@ namespace keepass2android
 		}
 	}
 
-	public abstract class FingerprintCrypt: FingerprintManager.AuthenticationCallback
+	public abstract class FingerprintCrypt: FingerprintManager.AuthenticationCallback, IFingerprintIdentifier
 	{
 		protected const string FailedToInitCipher = "Failed to init Cipher";
 		public override void OnAuthenticationError(FingerprintState errorCode, ICharSequence errString)
@@ -157,7 +163,9 @@ namespace keepass2android
 			
 		}
 
-		public abstract bool InitCipher();
+		public abstract bool Init();
+		
+
 		protected static string GetAlias(string keyId)
 		{
 			return "keepass2android." + keyId;
@@ -175,6 +183,11 @@ namespace keepass2android
 			}
 		}
 
+		public void StartListening(Context ctx, IFingerprintAuthCallback callback)
+		{
+			StartListening(new FingerprintAuthCallbackAdapter(callback, ctx));
+		}
+
 		public void StartListening(FingerprintManager.AuthenticationCallback callback)
 		{
 			if (!IsFingerprintAuthAvailable)
@@ -227,6 +240,13 @@ namespace keepass2android
 		}
 	}
 
+	public interface IFingerprintIdentifier
+	{
+		bool Init();
+		void StartListening(Context ctx, IFingerprintAuthCallback callback);
+		void StopListening();
+	}
+
 	public class FingerprintDecryption : FingerprintCrypt
 	{
 		private readonly Context _context;
@@ -245,9 +265,9 @@ namespace keepass2android
 			_iv = Base64.Decode(PreferenceManager.GetDefaultSharedPreferences(context).GetString(GetIvPrefKey(prefKey), null), 0);
 		}
 
-		public override bool InitCipher()
+		public override bool Init()
 		{
-			Kp2aLog.Log("FP: InitCipher for Dec");
+			Kp2aLog.Log("FP: Init for Dec");
 			try
 			{
 				_keystore.Load(null);
@@ -355,9 +375,9 @@ namespace keepass2android
 			}
 		}
 
-		public override bool InitCipher()
+		public override bool Init()
 		{
-			Kp2aLog.Log("FP: InitCipher for Enc ");
+			Kp2aLog.Log("FP: Init for Enc ");
 			try
 			{
 				_keystore.Load(null);

src/keepass2android/FingerprintSamsungIdentifier.cs

@@ -0,0 +1,141 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+using Android.App;
+using Android.Content;
+using Android.OS;
+using Android.Runtime;
+using Android.Util;
+using Android.Views;
+using Android.Widget;
+using Com.Samsung.Android.Sdk;
+using Com.Samsung.Android.Sdk.Pass;
+using Java.Lang;
+
+namespace keepass2android
+{
+	class FingerprintSamsungIdentifier: IFingerprintIdentifier
+	{
+		SpassFingerprint _spassFingerprint;
+		Spass _spass;
+		public FingerprintSamsungIdentifier(Context context)
+		{
+			_spass = new Spass();
+
+			try
+			{
+				_spass.Initialize(context);
+			}
+			catch (SecurityException)
+			{
+				//"Did you add the permission to the AndroidManifest.xml?");
+				throw;
+			}
+
+			if (_spass.IsFeatureEnabled(Spass.DeviceFingerprint))
+			{
+				_spassFingerprint = new SpassFingerprint(context);
+			}
+			else
+			{
+				throw new RuntimeException("Fingerprint Featue not available.");
+			}
+
+
+		}
+
+		public bool Init()
+		{
+			try
+			{
+				return _spassFingerprint.HasRegisteredFinger;
+			}
+			catch (UnsupportedOperationException)
+			{
+				return false;
+			}
+			
+			
+		}
+		class IdentifyListener : Java.Lang.Object, IIdentifyListener
+		{
+			private readonly IFingerprintAuthCallback _callback;
+			private readonly Context _context;
+			private readonly FingerprintSamsungIdentifier _id;
+
+
+			public IdentifyListener(IFingerprintAuthCallback callback, Context context, FingerprintSamsungIdentifier id)
+			{
+				_callback = callback;
+				_context = context;
+				_id = id;
+			}
+
+			
+
+			public void OnFinished (int responseCode)
+			{
+				_id.Listening = false;
+				if (responseCode == SpassFingerprint.StatusAuthentificationSuccess) 
+				{
+					_callback.OnFingerprintAuthSucceeded();
+				} 
+				else if (responseCode == SpassFingerprint.StatusAuthentificationPasswordSuccess) 
+				{
+					_callback.OnFingerprintAuthSucceeded();
+				} 
+				
+			}
+
+			public void OnReady ()
+			{
+				
+			}
+
+			public void OnStarted ()
+			{
+				
+			}
+		}
+
+		internal bool Listening
+		{
+			get; set;
+		}
+
+
+		public void StartListening(Context ctx, IFingerprintAuthCallback callback)
+		{
+			if (Listening) return;
+
+			try 
+			{
+				_spassFingerprint.StartIdentifyWithDialog(ctx, new IdentifyListener(callback, ctx, this), false);
+				Listening = true;
+			} 
+			catch (SpassInvalidStateException m)
+			{
+				callback.OnFingerprintError(m.Message);
+			} 
+			catch (IllegalStateException ex) 
+			{
+				callback.OnFingerprintError(ex.Message);
+			}
+		}
+
+		public void StopListening()
+		{
+			try
+			{
+				_spassFingerprint.CancelIdentify();
+				Listening = false;
+			}
+			catch (IllegalStateException ise)
+			{
+				Kp2aLog.Log(ise.Message);
+			}
+		}
+	}
+}

src/keepass2android/FingerprintSetupActivity.cs

@@ -24,7 +24,7 @@ namespace keepass2android
 		ConfigurationChanges = ConfigChanges.Orientation | ConfigChanges.KeyboardHidden,
 		Theme = "@style/MyTheme_ActionBar", MainLauncher = false)]
 	[IntentFilter(new[] { "kp2a.action.FingerprintSetupActivity" }, Categories = new[] { Intent.CategoryDefault })]
-	public class FingerprintSetupActivity : LockCloseActivity
+	public class FingerprintSetupActivity : LockCloseActivity, IFingerprintAuthCallback
 	{
 		private readonly ActivityDesign _activityDesign;
 
@@ -119,8 +119,29 @@ namespace keepass2android
 			FindViewById(Resource.Id.radio_buttons).Visibility = ViewStates.Gone;
 			FindViewById(Resource.Id.fingerprint_auth_container).Visibility = ViewStates.Gone;
 
-			if ((int)Build.VERSION.SdkInt >= 23)
-				RequestPermissions(new[] { Manifest.Permission.UseFingerprint }, FingerprintPermissionRequestCode);
+			if ((int) Build.VERSION.SdkInt >= 23)
+				RequestPermissions(new[] {Manifest.Permission.UseFingerprint}, FingerprintPermissionRequestCode);
+			else
+			{
+				try
+				{
+					//try to create a Samsung ID object 
+					_samsungFingerprint = new FingerprintSamsungIdentifier(this);
+					if (!_samsungFingerprint.Init())
+					{
+						SetError(Resource.String.fingerprint_no_enrolled);
+					}
+					ShowRadioButtons();
+				}
+				catch (Exception)
+				{
+					_samsungFingerprint = null;
+				}
+				
+			}
+			FindViewById(Resource.Id.container_fingerprint_unlock).Visibility = _samsungFingerprint == null
+				? ViewStates.Visible
+				: ViewStates.Gone;
 		}
 
 		string CurrentPreferenceKey
@@ -181,18 +202,32 @@ namespace keepass2android
 					SetError(Resource.String.fingerprint_no_enrolled);
 					return;
 				}
-				FindViewById<TextView>(Resource.Id.tvFatalError).Visibility = ViewStates.Gone;
-				FindViewById(Resource.Id.radio_buttons).Visibility = ViewStates.Visible;
-				FindViewById(Resource.Id.fingerprint_auth_container).Visibility = ViewStates.Gone;
+				ShowRadioButtons();
 			}
 		}
 
+		private void ShowRadioButtons()
+		{
+			FindViewById<TextView>(Resource.Id.tvFatalError).Visibility = ViewStates.Gone;
+			FindViewById(Resource.Id.radio_buttons).Visibility = ViewStates.Visible;
+			FindViewById(Resource.Id.fingerprint_auth_container).Visibility = ViewStates.Gone;
+		}
+
 
 		private void ChangeUnlockMode(FingerprintUnlockMode oldMode, FingerprintUnlockMode newMode)
 		{
 			if (oldMode == newMode)
 				return;
 
+			if (_samsungFingerprint != null)
+			{
+				_unlockMode = newMode;
+				ISharedPreferencesEditor edit = PreferenceManager.GetDefaultSharedPreferences(this).Edit();
+				edit.PutString(App.Kp2a.GetDb().CurrentFingerprintModePrefKey, _unlockMode.ToString());
+				edit.Commit();
+				return;
+			}
+
 			if (newMode == FingerprintUnlockMode.Disabled)
 			{
 				_unlockMode = newMode;
@@ -207,10 +242,10 @@ namespace keepass2android
 			_enc = new FingerprintEncryption(new FingerprintModule(this), CurrentPreferenceKey);
 			try
 			{
-				if (!_enc.InitCipher())
+				if (!_enc.Init())
 					throw new Exception("Failed to initialize cipher");
 				ResetErrorTextRunnable();
-				_enc.StartListening(new SetupCallback(this));
+				_enc.StartListening(new FingerprintAuthCallbackAdapter(this, this));
 			}
 			catch (Exception e)
 			{
@@ -227,7 +262,10 @@ namespace keepass2android
 		static readonly long SUCCESS_DELAY_MILLIS = 1300;
 		private ImageView _fpIcon;
 		private TextView _fpTextView;
-		public void OnAuthSucceeded()
+		
+		private FingerprintSamsungIdentifier _samsungFingerprint;
+
+		public void OnFingerprintAuthSucceeded()
 		{
 			_unlockMode = _desiredUnlockMode;
 
@@ -248,6 +286,7 @@ namespace keepass2android
 		}
 
 
+		
 		public void OnFingerprintError(string error)
 		{
 			_fpIcon.SetImageResource(Resource.Drawable.ic_fingerprint_error);
@@ -270,7 +309,7 @@ namespace keepass2android
 		{
 			base.OnResume();
 			if (_enc != null)
-				_enc.StartListening(new SetupCallback(this));
+				_enc.StartListening(new FingerprintAuthCallbackAdapter(this, this));
 		}
 
 		protected override void OnPause()
@@ -281,33 +320,4 @@ namespace keepass2android
 		}
 	}
 
-	internal class SetupCallback : FingerprintManager.AuthenticationCallback
-	{
-		private readonly FingerprintSetupActivity _fingerprintSetupActivity;
-
-		public SetupCallback(FingerprintSetupActivity fingerprintSetupActivity)
-		{
-			_fingerprintSetupActivity = fingerprintSetupActivity;
-		}
-
-		public override void OnAuthenticationSucceeded(FingerprintManager.AuthenticationResult result)
-		{
-			_fingerprintSetupActivity.OnAuthSucceeded();
-		}
-
-		public override void OnAuthenticationError(FingerprintState errorCode, ICharSequence errString)
-		{
-			_fingerprintSetupActivity.OnFingerprintError(errString.ToString());
-		}
-
-		public override void OnAuthenticationHelp(FingerprintState helpCode, ICharSequence helpString)
-		{
-			_fingerprintSetupActivity.OnFingerprintError(helpString.ToString());
-		}
-
-		public override void OnAuthenticationFailed()
-		{
-			_fingerprintSetupActivity.OnFingerprintError(_fingerprintSetupActivity.Resources.GetString(Resource.String.fingerprint_not_recognized));
-		}
-	}
 }

src/keepass2android/KeeChallenge.cs

@@ -64,8 +64,7 @@ namespace KeeChallenge
 
         private byte[] GenerateChallenge()
         {
-            CryptoRandom rand = CryptoRandom.Instance;
-            byte[] chal = CryptoRandom.Instance.GetRandomBytes(challengeLenBytes);
+	        byte[] chal = CryptoRandom.Instance.GetRandomBytes(challengeLenBytes);
             if (LT64)
             {
                 chal[challengeLenBytes - 2] = (byte)~chal[challengeLenBytes - 1];

src/keepass2android/PasswordActivity.cs

@@ -700,6 +700,7 @@ namespace keepass2android
 		private ActivityDesign _activityDesign;
 		private FingerprintDecryption _fingerprintDec;
 		private bool _fingerprintPermissionGranted;
+		private PasswordActivityBroadcastReceiver _intentReceiver;
 
 
 		internal class MyActionBarDrawerToggle : ActionBarDrawerToggle
@@ -757,6 +758,11 @@ namespace keepass2android
 			_activityDesign.ApplyTheme();
 			base.OnCreate(savedInstanceState);
 
+			_intentReceiver = new PasswordActivityBroadcastReceiver(this);
+			IntentFilter filter = new IntentFilter();
+			filter.AddAction(Intent.ActionScreenOff);
+			RegisterReceiver(_intentReceiver, filter);
+			
 			
 			//use FlagSecure to make sure the last (revealed) character of the master password is not visible in recent apps
 			if (PreferenceManager.GetDefaultSharedPreferences(this).GetBoolean(
@@ -1800,7 +1806,7 @@ namespace keepass2android
 
 				btn.Tag = GetString(Resource.String.fingerprint_unlock_hint);
 
-				if (_fingerprintDec.InitCipher())
+				if (_fingerprintDec.Init())
 				{
 					btn.SetImageResource(Resource.Drawable.ic_fp_40px);
 					_fingerprintDec.StartListening(new FingerprintAuthCallbackAdapter(this, this));
@@ -2044,13 +2050,36 @@ namespace keepass2android
 
 			}
 		}
+		private class PasswordActivityBroadcastReceiver : BroadcastReceiver
+		{
+			readonly PasswordActivity _activity;
+			public PasswordActivityBroadcastReceiver(PasswordActivity activity)
+			{
+				_activity = activity;
+			}
 
+			public override void OnReceive(Context context, Intent intent)
+			{
+				switch (intent.Action)
+				{
+					case Intent.ActionScreenOff:
+						Kp2aLog.Log("bla");
+						_activity.OnScreenLocked();
+						break;
+				}
+			}
+		}
+
+		private void OnScreenLocked()
+		{
+			if (_fingerprintDec != null)
+				_fingerprintDec.StopListening();
+			
+		}
 	}
 
-	public interface IFingerprintAuthCallback
-	{
-		void OnFingerprintAuthSucceeded();
-		void OnFingerprintError(string toString);
-	}
+
+
+	
 }
 

src/keepass2android/Properties/AndroidManifest_debug.xml

@@ -99,4 +99,6 @@
 	<uses-permission android:name="android.permission.MANAGE_ACCOUNTS" />
 	<uses-permission android:name="keepass2android.keepass2android_debug.permission.KP2aInternalFileBrowsing" />
 	<uses-permission android:name="android.permission.USE_FINGERPRINT" />
+	<!-- Samsung Pass permission -->
+	<uses-permission android:name="com.samsung.android.providers.context.permission.WRITE_USE_APP_FEATURE_SURVEY" />
 </manifest>

src/keepass2android/Properties/AndroidManifest_net.xml

@@ -102,4 +102,6 @@
 	<uses-permission android:name="android.permission.MANAGE_ACCOUNTS" />
 	<uses-permission android:name="keepass2android.keepass2android.permission.KP2aInternalFileBrowsing" />
 	<uses-permission android:name="android.permission.USE_FINGERPRINT" />
+	<!-- Samsung Pass permission -->
+	<uses-permission android:name="com.samsung.android.providers.context.permission.WRITE_USE_APP_FEATURE_SURVEY" />
 </manifest>

src/keepass2android/Properties/AndroidManifest_nonet.xml

@@ -80,4 +80,6 @@
 	<uses-permission android:name="android.permission.VIBRATE" />
 	<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
 	<uses-permission android:name="android.permission.USE_FINGERPRINT" />
+	<!-- Samsung Pass permission -->
+	<uses-permission android:name="com.samsung.android.providers.context.permission.WRITE_USE_APP_FEATURE_SURVEY" />
 </manifest>

src/keepass2android/QuickUnlock.cs

@@ -43,7 +43,7 @@ namespace keepass2android
 		private QuickUnlockBroadcastReceiver _intentReceiver;
 		private ActivityDesign _design;
 		private bool _fingerprintPermissionGranted;
-		private FingerprintDecryption _fingerprintDec;
+		private IFingerprintIdentifier _fingerprintIdentifier;
 		private int _quickUnlockLength;
 		private const int FingerprintPermissionRequestCode = 0;
 
@@ -139,8 +139,12 @@ namespace keepass2android
 			filter.AddAction(Intents.DatabaseLocked);
 			RegisterReceiver(_intentReceiver, filter);
 
-			if ((int)Build.VERSION.SdkInt >= 23)
-				RequestPermissions(new[] { Manifest.Permission.UseFingerprint }, FingerprintPermissionRequestCode);
+			if ((int) Build.VERSION.SdkInt >= 23)
+				RequestPermissions(new[] {Manifest.Permission.UseFingerprint}, FingerprintPermissionRequestCode);
+			else
+			{
+				
+			}
 
 		}
 
@@ -176,7 +180,7 @@ namespace keepass2android
 
 		public void OnFingerprintAuthSucceeded()
 		{
-			_fingerprintDec.StopListening();
+			_fingerprintIdentifier.StopListening();
 			var btn = FindViewById<ImageButton>(Resource.Id.fingerprintbtn);
 
 			btn.SetImageResource(Resource.Drawable.ic_fingerprint_success);
@@ -207,23 +211,42 @@ namespace keepass2android
 					return;
 				}
 
-				FingerprintModule fpModule = new FingerprintModule(this);
-				_fingerprintDec = new FingerprintDecryption(fpModule, App.Kp2a.GetDb().CurrentFingerprintPrefKey, this,
-					App.Kp2a.GetDb().CurrentFingerprintPrefKey);
-
+				if (_fingerprintPermissionGranted)
+				{
+					FingerprintModule fpModule = new FingerprintModule(this);
+					_fingerprintIdentifier = new FingerprintDecryption(fpModule, App.Kp2a.GetDb().CurrentFingerprintPrefKey, this,
+						App.Kp2a.GetDb().CurrentFingerprintPrefKey);
+				}
+				else
+				{
+					try
+					{
+						_fingerprintIdentifier = new FingerprintSamsungIdentifier(this);
+						btn.Click += (sender, args) =>
+						{
+							if (_fingerprintIdentifier.Init())
+								_fingerprintIdentifier.StartListening(this, this);
+						};
+					}
+					catch (Exception)
+					{
+						FindViewById<ImageButton>(Resource.Id.fingerprintbtn).Visibility = ViewStates.Gone;
+						return;	
+					}
+				}
 				btn.Tag = GetString(Resource.String.fingerprint_unlock_hint);
 
-				if (_fingerprintDec.InitCipher())
+				if (_fingerprintIdentifier.Init())
 				{
 					btn.SetImageResource(Resource.Drawable.ic_fp_40px);
-					_fingerprintDec.StartListening(new FingerprintAuthCallbackAdapter(this, this));
+					_fingerprintIdentifier.StartListening(this, this);
 				}
 				else
 				{
 					//key invalidated permanently
 					btn.SetImageResource(Resource.Drawable.ic_fingerprint_error);
 					btn.Tag = GetString(Resource.String.fingerprint_unlock_failed);
-					_fingerprintDec = null;
+					_fingerprintIdentifier = null;
 
 					ClearFingerprintUnlockData();
 				}
@@ -233,7 +256,7 @@ namespace keepass2android
 				btn.SetImageResource(Resource.Drawable.ic_fingerprint_error);
 				btn.Tag = "Error initializing Fingerprint Unlock: " + e;
 
-				_fingerprintDec = null;
+				_fingerprintIdentifier = null;
 			}
 
 
@@ -294,23 +317,17 @@ namespace keepass2android
 				}, 50);
 
 
-			if (_fingerprintPermissionGranted)
-			{
-				InitFingerprintUnlock();
-			}
-			else
-			{
-				FindViewById<ImageButton>(Resource.Id.fingerprintbtn).Visibility = ViewStates.Gone;
 			
-			}
+			InitFingerprintUnlock();
+			
 		}
 
 		protected override void OnPause()
 		{
 			base.OnPause();
-			if (_fingerprintDec != null)
+			if (_fingerprintIdentifier != null)
 			{
-				_fingerprintDec.StopListening();
+				_fingerprintIdentifier.StopListening();
 			}
 		}
 

src/keepass2android/Resources/layout/fingerprint_setup.xml

@@ -50,6 +50,7 @@
         </LinearLayout>
         <LinearLayout
             android:orientation="horizontal"
+            android:id="@+id/container_fingerprint_unlock"
             android:layout_width="fill_parent"
             android:layout_height="wrap_content">
             <RadioButton

src/keepass2android/keepass2android.csproj

@@ -136,6 +136,7 @@
     <Compile Include="EntryActivityClasses\ToggleVisibilityPopupMenuItem.cs" />
     <Compile Include="EntryActivityClasses\WriteBinaryToFilePopupItem.cs" />
     <Compile Include="FingerprintModule.cs" />
+    <Compile Include="FingerprintSamsungIdentifier.cs" />
     <Compile Include="FingerprintSetupActivity.cs" />
     <Compile Include="ExportDatabaseActivity.cs" />
     <Compile Include="fileselect\FileChooserFileProvider.cs" />
@@ -756,6 +757,10 @@
       <Project>{3DA3911E-36DE-465E-8F15-F1991B6437E5}</Project>
       <Name>PluginSdkBinding</Name>
     </ProjectReference>
+    <ProjectReference Include="..\SamsungPass\Xamarin.SamsungPass\SamsungPass\SamsungPass.csproj">
+      <Project>{3a4b8e88-fa9b-4663-bcda-21c12e3af98a}</Project>
+      <Name>SamsungPass</Name>
+    </ProjectReference>
     <ProjectReference Include="..\TwofishCipher\TwofishCipher.csproj">
       <Project>{5CF675A5-9BEE-4720-BED9-D5BF14A2EBF9}</Project>
       <Name>TwofishCipher</Name>